Add dummy and LevelDB database backends

src/leveldb/db/write_batch_internal.h

@@ -0,0 +1,49 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_
+#define STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_
+
+#include "leveldb/write_batch.h"
+
+namespace leveldb {
+
+class MemTable;
+
+// WriteBatchInternal provides static methods for manipulating a
+// WriteBatch that we don't want in the public WriteBatch interface.
+class WriteBatchInternal {
+ public:
+  // Return the number of entries in the batch.
+  static int Count(const WriteBatch* batch);
+
+  // Set the count for the number of entries in the batch.
+  static void SetCount(WriteBatch* batch, int n);
+
+  // Return the seqeunce number for the start of this batch.
+  static SequenceNumber Sequence(const WriteBatch* batch);
+
+  // Store the specified number as the seqeunce number for the start of
+  // this batch.
+  static void SetSequence(WriteBatch* batch, SequenceNumber seq);
+
+  static Slice Contents(const WriteBatch* batch) {
+    return Slice(batch->rep_);
+  }
+
+  static size_t ByteSize(const WriteBatch* batch) {
+    return batch->rep_.size();
+  }
+
+  static void SetContents(WriteBatch* batch, const Slice& contents);
+
+  static Status InsertInto(const WriteBatch* batch, MemTable* memtable);
+
+  static void Append(WriteBatch* dst, const WriteBatch* src);
+};
+
+}  // namespace leveldb
+
+
+#endif  // STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_